The semiconductor industry has progressed into nanometer technology process nodes in pursuit of higher device density, higher performance, and lower costs. Despite groundbreaking advances in materials and fabrication, scaling planar device such as the conventional MOSFET has proven challenging. To overcome these challenges, circuit designers look to novel structures to deliver improved performance. One avenue of inquiry is the development of three-dimensional designs, such as a fin-like field effect transistor (FinFET). A FinFET can be thought of as a typical planar device extruded out of a substrate and into the gate. A typical FinFET is fabricated with a thin “fin” (or fin structure) extending up from a substrate. The channel of the FET is formed in this vertical fin, and a gate is provided over (e.g., wrapping around) the channel region of the fin. Wrapping the gate around the fin increases the contact area between the channel region and the gate and allows the gate to control the channel from multiple sides. This can be leveraged in a number of way, and in some applications, FinFETs provide reduced short channel effects, reduced leakage, and higher current flow. In other words, they may be faster, smaller, and more efficient than planar devices.
However, because of the complexity inherent in FinFETS and other non-planar devices, fabrication techniques may more closely resemble MEMS (microelectromechanical systems) techniques than conventional planar transistor fabrication. Some planar techniques may be redesigned for non-planar manufacturing. Other techniques are wholly unique to non-planar fabrication. Thus while non-planar devices have already proven suitable for a number of applications, opportunities remain for further advances in device structures, materials, and fabrication techniques. These advances have the potential to deliver further reductions in power and size with improved drive strength and reliability.